Device for influencing gas flows

ABSTRACT

The invention relates to a device for controlling and guiding gas flow in atomizers, in breathing and rebreathing regions of a respiratory appliance. A first embodiment comprises a bypass device; and a said second embodiment comprises a valve which is timed by the respiratory appliance, such that the dead space is not filled with aerosol. Both embodiments provide for an application of aerosol only in the inspiration phase, reduction of the applied medication quantity by reducing the atomization of the dead space, reduction of the side effects of the medications, and sufficient moisturizing of the airways.

FIELD OF THE INVENTION

This invention relates to respirator appliances and specifically tocontrolling and guiding the flow of gas within such appliances.

BACKGROUND OF THE INVENTION

With patients suffering from pulmonary diseases, aerosols are often usedfor therapy. However, special difficulties arise with the utilization ofaerosols with patients receiving artificial respiration. Eithercompressed-air operated nozzle atomizers or atomizers producing aerosolscontinuously, such as, e.g., ultrasound atomizers or piezoelectricatomizers are used. The nozzle atomizers are normally placed in thecommon end segment for inspiration and expiration of the artificialrespiration hoses, shortly before the tube barrel and are controlled viathe artificial respirator, so that they are active only duringinspiration. An atomizer is, however, active until the end ofinspiration, so that in the overall hose system distal gas enriched withaerosol is present in the atomizer so that the dead-space volume is alsoprovided with aerosol. Thus, it is possible as a rule to place abacterial filter between the inspiration or expiration legs and the tubebarrel, playing also a role in humidifying the respiratory tracts. Theheavy humidification of the non-utilized gas column (dead space volume),mostly with large aerosol particles, causes the filter to become filledwith liquid and thus loses its antibacterial effect on the one hand,while, on the other hand, the resistance of the filter increases so muchthat it closes up.

The continuous atomizers such as, e.g., ultrasound atomizers orpiezoelectric atomizers produce smaller particles (average size lessthan 7 μm) that reach the point of utilization more easily, resulting infewer side effects and lower drug costs. However, these devices can onlybe placed in the inspiration leg of an artificial respirator since theyproduce aerosols continuously and would thus convey aerosols to or fromthe patient during the inspiration as well as during the expirationphase. A filter would, therefore, fill up and lose effectiveness orclose up. By omitting a filter, insufficient humidification of thebreathing or inhaled air results so that a breathing-air humidifier hasto be used which, in addition to costs, also involves a hygienic problem(nosocomial pneumonia). Accordingly, an object of the invention is tocreate a device in combination with aerosol-producing atomizers that canavoid the foregoing described problems.

SUMMARY OF THE INVENTION

The above object of the invention is attained by means of a device forcontrolling the direction of gas flow in aerosol producing atomizers inthe inspiration and expiration breathing zones of a respirator, with abypass device which guides the gas as it flows in one direction throughthe atomizer in order to carry with it aerosol and which guides ordiverts the gas past the atomizer via a bypass as it flows in the otherdirection.

In another aspect the invention is a device to direct the gas flow inatomizers in the inspiration and expiration phases of a respirator bymeans of a valve that is time-controlled by the respirator and closesbefore the end of the inspiration function so as not to fill the deadspace volume with aerosol.

DESCRIPTION OF THE DRAWINGS

In the drawings appended hereto and made a part of this disclosure byway of illustration and not by way of limitation:

FIG. 1 a is a schematic representation of a respiratory appliance havingan atomizer showing the arrangement of valves for gas flow in theinspiration phase;

FIG. 1 b is the representation of FIG. 1 a showing the gas flow in theexpiration phase;

FIG. 2 a is a schematic representation similar to FIG. 1 a showingcontrol of the flow valve by the respirator during the inspirationphase; and,

FIG. 2 b shows the representation of FIG. 2 a during the expirationphase.

DETAILED DESCRIPTION

My invention makes it possible to place the atomizer (any atomizer canbe used) between a filter and tube barrel without a breathing airhumidifier at the common end segment of a respirator with the advantageof lower consumption of medicine, fewer side-effects due to appliedmedicines and longer life of the filter. This is done in the followingmanner in one embodiment:

The breathing air is conveyed through an atomizer via closing valves(passively or actively controlled as indicated). To make this possible,the valves can be placed at different points in this device. Thepossibility also exists to use auxiliary devices (e.g., ventilators) inorder to optimize the distribution of the aerosol.

In another embodiment, a control cable or hose causes a valve to open inresponse to the volume of breath, the duration of inspiration, and thepressure of inspiration, so that the dead space is not filled withaerosol. The possibility also exists in this embodiment to use auxiliarydevices (e.g., ventilators) to optimize the distribution of the aerosol.

The invention is described in greater detail below with reference to thedrawings:

FIG. 1 a is a schematic diagram of respiratory appliance A or respiratorand showing the placement of aerosol producing atomizers 3 (any kind ofatomizer can be used) between filter 6 and connection element going tothe pipe barrel 7 without breathing-air humidifier at the common endsegment (1). This is achieved in that the breathing air is taken throughvalves (2, 4) (any possible types of valves can be used). During theinspiration phase in FIG. 1 a the valve 2 opens and the valve 4 closes(under passive or active control), so that the breathing air (air flowarrow, F) is guided through the atomizer 3. In expiration (FIG. 1 b)valve 2 closes and valve 4 opens and the air flow F is guided throughbypass 5, 5′ avoiding atomizer 3. To make this possible the valves canbe placed at different points in this arrangement, e.g., the inspirationvalve can be between input and output of the bypass, or the expirationvalve can be in the entire bypass. The inspiration leg of the respiratorhose is given reference number 7, the expiration leg number 8.

FIGS. 2 a, b shows a second embodiment in which any atomizer can be usedand which opens valve 12 (any possible type of valve can be used) via acontrol cable or hose 14 during inspiration for the desired time inresponse to breath volume, inspiration duration, and inspirationpressure, under control of the respirator 15 (FIG. 2 a). At the end ofthe inspiration phase and in the expiration phase the valve 12 closes sothat the dead space volume is not filled with aerosol (FIG. 2 b). Number6 refers to the filter. The inspiration leg of the respirator hose isreferenced by number 7 and the expiration leg by number 8.

1. A device for controlling the direction of gas or air flow in anin-and-out breathing zone of a respirator which has a patient side endsegment, said device comprising: a) a single filter for filtering bothinspirator and expirator air; b) an aerosol producing atomizerpositioned in said breathing zone between said filter and said endsegment, c) by-pass valve means adjacent said atomizer for guiding airthrough the atomizer as the air flows in one direction to the patientand for by-passing said atomizer as air flows in the other direction. 2.A device for controlling air or gas flow in an aerosol producingatomizer positioned in an in-and-out breathing zone of a respiratorhaving a patient side end segment, said device comprising: a) a by-passvalve, said valve being time controlled by the respirator to close andprevent aerosol from filling the dead space volume, and b) a singlefilter for both the inspiration and expiration of air, said atomizerbeing located between said filter and said patient side end segment sothat the patient end segment is close to the atomizer.